A vigorous 67 when World War II began, Keyes staunchly supported First Lord of the Admiralty Winston L. S. Churchill's ill-considered efforts in Norway in 1940. His parliamentary speech of 7 May 1940, criticizing the government's record, helped cause the fall of Prime Minister Neville Chamberlain and his replacement by Churchill. Three days later, Keyes became British liaison officer to King Leopold III of Belgium, until the latter signed an armistice with Germany on 27 May 1940.
In July 1940, Churchill appointed Keyes director of Combined Operations. As such, he was responsible for the early planning of British efforts to return to continental Europe, including organizing a special force of commandos intended to mount unconventional secret raids against enemy targets. He expanded this organization substantially and won it considerable independence from supervision by the army, navy, marines, and air force. In autumn 1941, however, Churchill's decree that Keyes should not "direct" commando operations but simply organize and train the units and advise as to their use led the infuriated admiral to resign, and Lord Louis Mountbatten replaced him. In late November, Keyes's son Geoffrey died in an unsuccessful commando raid intended to assassinate German General Erwin Rommel, winning the Victoria Cross.
Although Keyes criticized the government's handling of the war in Parliament, he was made a peer, Baron Keyes of Zeebrugge and Dover, in January 1943. He undertook minor government assignments thereafter and lectured in the United States, Canada, Australia, and New Zealand in the summer of 1944; he subsequently observed the Leyte landings in the Philippines. Keyes died in Buckingham, England, on 26 December 1945.
Aspinall-Oglander, C. F. Roger Keyes. London: Hogarth Press, 1951.; Fergusson, Bernard. The Watery Maze: The Story of Combined Operations. New York: Holt, Rinehart and Winston, 1961.; Keyes, Roger. Amphibious Warfare and Combined Operations. Cambridge: Cambridge University Press, 1943.; Keyes, Roger. The Keyes Papers: Selections from the Private and Official Correspondence of Admiral of the Fleet Baron Keyes of Zeebrugge. 2 vols. London: George Allen and Unwin, 1972–1980.; Roskill, Stephen. Churchill and the Admirals. New York: William Morrow, 1978.